Instruments and methods for subperiosteal tunneling and related surgical procedures

ABSTRACT

The present invention is a group of surgical instruments with improved function and design for dental and craniofacial surgery, especially subperiosteal tunneling and related procedures. The instruments include surgical elevators for vestibular incision or incisions in the gingival sulcus. The instruments have varying angles and shapes to create a mucosal tunnel in any oral or maxillofacial region. The instrument suite also optionally includes specially designed forceps for introduction of graft material inside the subperiosteal tunnel and to assist with suturing of the graft to surrounding tissue.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is related to and claims priority of U.S. provisionalapplication (“Provisional Application”), Ser. No. 62/617,093, filed Jan.12, 2018, entitled “Instruments and Methods for Subperiosteal Tunnelingand Related Surgical Procedures.” The priority of this application isexpressly claimed, and the disclosure is hereby incorporated byreference in their entirety.

BACKGROUND OF THE INVENTION

Mucosal surgery operations are common to treat dental and craniofacialdisorders. Traditionally, mucosal surgical procedures require largeincisions and reflection of a region of tissue called the mucoperiostealflaps. These large flaps contain the vascular supply and are crucial tomaintain the health of the mucosal tissue and surrounding structures.Large incisions and pronounced reflection of mucoperiosteal flaps causedelayed healing, excessive pain, inflammation, and the potential foredema. Traditional mucoperiosteal flap procedures often produceunsatisfactory results because of scar formation and negative aestheticconsequences. Moreover, the healing pattern can be unpredictable andlead to excess scar tissue, gingival recession, necrosis, and othernegative outcomes.

For these reasons, procedures that enable minimally invasive tunnelingthrough mucosal tissue have been proposed as a way of reducing surgicaltrauma from conventional flap surgery. Tunnel surgery includes making amuch smaller incision at an access site remote from the therapeutictarget. Once the precise access incision away from the target site ismade, the surgeon creates a submucosal tunnel to access the tissue andbone at the surgical site. Once the incision and submucosal tunnel aremade, access is obtained by introducing a range of instruments throughthe incision, traversing the length of the submucosal tunnel, andbringing the functional ends of the instruments to the targettherapeutic area.

Subperiosteal tunnel surgery can be performed through several routes andmethods. The access for the tunnel can be made through either thegingival sulcus or through a vestibular incision. A gingival sulculartunnel has the disadvantage of limited access through the very smallgingival sulcus. In particular, in the presence of exostosis, thesulcular tunnel route is very challenging to the surgeon. Vestibularaccess offers a much wider access area, which is technically easier butstill requires specialized instrumentation to perform the surgicalprocedure while reducing trauma to the surrounding tissues. There arebroadly two kinds of tunnel, namely subperiosteal (full-thickness) andsupra-periosteal (split- or partial-thickness) tunnel. Supra-periostealtunnel requires sharp dissection, while subperiosteal tunnel requiresblunt dissection. In order to efficiently perform subperiostealtunneling, mucoperiosteal complex has to be elevated from underlyingbone.

Although clear advantages of this surgical technique exist, suchprocedures are very challenging for the surgeon because the entiresurgery has to be performed through the small access incision.Therefore, these procedures would be improved and be more widelypractices if specialized instruments were developed that allow efficientseparation of tissue from bone and elevation of tissue to create asubmucosal tunnel allowing the introduction of other therapeuticsinstruments while minimizing trauma.

SUMMARY OF THE INVENTION

The present invention is a suite of instruments for improvedsubperiosteal tunneling procedures and improved methods for dental andcraniofacial surgery.

The elevator devices of the invention have a number of structural andoperational features that yield unique advantages for mucoperiostealcomplex reflection, including but not limited to the following:

-   -   1) the elevators feature an atraumatic flat tip to provide        increased contact between elevators and bone;    -   2) the elevators feature atraumatic rounded edges around the        periphery and at the distal edge of the flap tips. These        structures allow the tips to be slightly rotated to activate a        narrower tip, when necessary;    -   3) the tips of the elevators have a pre-determined curve        designed to engage bone along a length of the tip to avoid        puncturing the overlying mucosal tissue;    -   4) the elevators have an anodized dark color, which facilitates        visualization of the instrument through the tissue when        introduced through the tunnel; and    -   5) the elevators preferably have curved shanks with specific at        predetermined portions along their length angulations to        facilitate access to surgical areas; and    -   6) the handles of the elevators have an ergonomic design        allowing the surgeon to easily manipulate the instruments by        hand during a procedure.

Specially designed graft placement forceps have a number of featuresthat facilitate minimally invasive, atraumatic introduction andplacement of a graft though the tunnel. The graft forceps have a numberof structural and operational features that yield unique advantages forgraft placement, including but not limited to the following:

-   -   1) the forceps have exactly three prongs. Two grasping prongs        are actuated by hand to grasp the graft and inserted the graft        inside the tunnel. The third alignment prong aligns with the        first two prongs but is positioned over the exterior of the        tunnel. At least one and preferably all three of these three        prongs have a semi-circular eyelet at the tip for passage of        suture and needle. The tips align while simultaneously holding        the graft in position inside the tunnel. Once the graft is in        position a suture needle is passed through the surface mucosal        flap, as well as the graft to allow suturing the graft to the        flap.    -   2) The two grasping prongs each have teeth at the tip        strategically aligned and oriented away from the tip. This        design allows the graft being grasped by the pair of tips to be        inserted inside the tunnel and to remain securely held during        insertion. The orientation of the teeth also allows the forceps        to be retracted out of the tunnel and without displacing the        graft during removal of the forceps.    -   3) The forceps handles are designed to allow the surgeon to        press together only the first pair of prongs to hold the graft        without actuating the third handle, whose entire length remains        outside of the tunnel. Once the graft is positioned in place,        the third handle is actuated to bring the tip in contact with        the exterior of the tissue, aligned with the distal tip of the        other two prongs. This allows alignment of the three eyelets        together, while holding the graft inside the tunnel. The aligned        eyelets at the tips can are then used to pass a suture through        the surface mucosa and through the graft to attach the graft to        the mucosa.

The methods of the invention include introducing the unique elevatorsthrough the vestibule to efficiently perform subperiosteal tunnelingprocedures including the elevation of the mucoperiosteal complex fromunderlying bone. The methods also include use of the 3-prong forceps ofthe invention to introduce a graft through a minimally invasiveincision, advancing the graft to a target site, and graft placement. Themethods include using any of the unique devices of the invention toperform a surgical procedure, including but not limited to at thegingival margins to alleviate a diseased condition.

DESCRIPTION OF THE FIGURES

FIGS. 1A and 1B are an embodiment of the elevators of the inventionhaving a first elongated shaft region and a second elongated shaftregion oriented at an angle to one another and terminating in a curvedatraumatic tip.

FIG. 2 is an embodiment of an elevator of the invention having a firstelongated shaft, a curved transitional portion to a second shaft regionand optionally a second curved transitional portion and terminating in acurved atraumatic tip.

FIGS. 3A and 3B are embodiments of the elevator of the invention havingfirst, second, and third elongated shaft regions oriented atpredetermined angles to one another and to a handle for positioning of acurved atraumatic tip at a surgical site.

FIG. 4A and FIG. 4B are embodiments of the elevator of the inventionhaving three elongated shaft regions disposed in three different planesto permit advantageous orientation of a distal tip thereof at a surgicalsite.

FIG. 5 is an embodiment of the three-prong forceps of the inventionshowing the three individual handles having an eyelet at the distal tipthereof.

FIG. 6 is a side view of the three-prong forceps of the inventionshowing an orientation of the distal end of the forceps wherein a pairof the grasping prongs feature forward directed teeth for graftengagement and positioning, combined with atraumatic removal of theforceps, together with an alignment prong.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1A, the elevator 1 is comprised of a base portion 2that is comprised of a handle 2 or has a mating fixture (not shown) forattachment to a separate, reusable handle feature preferably having anergonomic grip. The elevator 1 has a first elongated shaft region 3 anda second elongated shaft region 4 wherein the first and second elongatedshaft regions are oriented by angle A having a range between 0° and 45°and terminate in a distal curved atraumatic tip 5. The outer edge 6 ofthe atraumatic tip 5 is rounded and curved to atraumatically engagetissue during a tunneling procedure. The distal end of the elevator 1 iscomprised of an arc region 9 that terminates in the atraumatic tip 5. Asis apparent from the side view of FIG. 1A, the atraumatic tip 5 isangled and curved relative to the second elongated shaft region 4 asindicated by the measurement of arc B. Arc B is preferably one-quartercircle but may range from a one-eighth circle to a one-half circle. Theembodiment of FIG. 1B is similar to the embodiment of the elevators ofFIG. 1A, but having an altered size of the distal atraumatic tip 5 for adifferent surgical application including altered lengths of the firstelongated shaft region 3 and the second elongated shaft region 4. Theembodiment of FIG. 1B, has a similar angle A reflecting the deflectionof the first elongated shaft 3 relative to the second elongated shaft 4and an extended arc region 9 as indicated by the arc measure C.

Referring to FIG. 2, an elevator of the invention 10 having handle 12also has a mating fixture (not shown) for attachment to a separate,reusable handle feature preferably having an ergonomic grip. Theelevator 10 has a proximal shaft region 13, a curved transitionalportion 14 connected to a second distal shaft region 15 and optionally asecond curved transitional portion 16 operably connected to a distalshaft region 17 and terminating in a curved atraumatic tip 18 a. Thefirst and second shaft regions 13, 15 are oriented by angle D having arange between 0° and 45° and the second shaft region 15 is oriented tothe first shaft region 13 by angle E also having a range between 0° and45°. In one embodiment the sum of angles D and B is approximately 180°.As with the embodiment of FIGS. 1A and 1B, the elevator terminates in anatraumatic tip 19 having a distal edge that is rounded and curved foratraumatic engagement of tissue during a tunneling procedure.

The distal end of the elevator 1 is comprised of an arc region 18 b thatterminates in the atraumatic tip 19. As is apparent from the side viewof FIG. 2, the atraumatic tip 19 is angled and curved relative to thesecond distal shaft region 4 as indicated by the measurement of arc F.Arc F is preferably one-quarter circle but may range from a one-eighthcircle to a one-half circle. The embodiments of FIG. 2 are similar tothe embodiment of the elevators of FIGS. 1A, 1B but having an alteredsize of the distal atraumatic tip 19 for a different surgicalapplication including altered lengths of the first proximal shaft region13 and the second distal shaft region 17. The embodiment of FIG. 1B, hasa similar angle A reflecting the deflection of the first elongated shaft3 relative to the second elongated shaft 4 and an extended arc region 18b indicated by the arc measure F.

Referring to FIG. 3A, an elevator embodiment of the present invention 20has a base portion 20, a first elongated shaft region 22, a first angle23, a second elongated shaft region 22 a, a second angle 24, and a thirdshaft region 25 that orients distal atraumatic tip 26 at a predeterminedangle relative to the normal line traversing the base portion 21 and thelength of the first shaft region 22. The first and second shaft regions22, 22 a are oriented around angle E (between 0° and 45°) and the secondand third shaft regions 22 a, 25 or oriented around angle F preferablygreater than 90° and less than 180°) to achieve the desired positioningof the atraumatic tip 26. In the second embodiment of FIG. 3B (lower,the first shaft region 22 and the second shaft region 22 a are orientedaround angle G and the second shaft region 22 a and the third shaftregion 25 are oriented around angle H. As with the prior embodiments,the atraumatic tip terminates in an outer edge that is rounded andcurved to be atraumatic to surrounding tissue during a tunnelingprocedure. Referring to FIG. 3B, a similar embodiment to the elevator ofFIG. 3A is shown having different dimensions and a similar set ofangular orientations, shaft regions and distal tip.

Referring to FIGS. 4A and 4B, elevators of the present invention mayemploy distinct shaft regions that are oriented in different planes toposition the atraumatic tip advantageously at the surgical site onceintroduced through an incision. Referring to FIGS. 4 A, 4B, the baseportion 31 is adjacent to first shaft region 32 that is at an angle Jrelative to the second shaft region 34 around junction 33 that alsoestablishes a first plane in which both of the first shaft region 32 andsecond shaft region 34 are disposed. Junction 35 orients the third shaftregion 36 at angle K relative to the second shaft region 34 and alsoorients the third shaft region 36 out of the plane in which the firstand second shaft regions 32, 34 are contained. A different alternativewould be to orient second shaft region 34 and third shaft region 36 inthe same plane while orienting the base portion 31 in the first shaftregion 32 in a separate plane relative to the plane containing thesecond and third shaft regions 34, 36. As with the embodiments describedabove, the third shaft region 36 terminates in an atraumatic tip 37having the characteristics described above. As with the foregoingembodiments, the atraumatic tip 37 may be curved along its length by arcL.

FIG. 5 is an embodiment of the three-prong forceps of the inventionshowing the three individual handles having an eyelet at the distal tipthereof. Referring to FIG. 5, the individual prongs 51, 61, 71 are shownseparately and detached to illustrate the differing shapes of the pairof grasping prongs 51, 61 and the alignment prong 71. Each prong 51, 61,71 is comprised of a handle portion 52, 62, 72 for operation by the handof the surgeon. In a preferred embodiment, the hand portion 52, 62 ofthe pair of grasping prongs 51, 61 have a similar shape for ease ofoperation. The handle portion 72 of the alignment prong 71 has adifferent shape, optionally effected by a cutout portion 73 of thealignment prong 71 relative to the handle portion 52, 62 of the graspingprongs 51, 61.

The distal end of each prong features a suture guide, 53, 63, 74 foralignment when the forceps are actuated by hand. In a preferredembodiment, the suture guide is a semi-circular eyelet 53, 63, 74 suchthat the suture guide portions are in alignment during operation of theforceps. As described above, the pair of grasping prongs 51, 61 engage agraft at the distal tip thereof proximate to the suture guide and areheld in close conformity to introduce the guide through a minimallyinvasive incision. The alignment probe 74 remains outside the incisionand is brought into conforming engagement on the opposite side of themucosal tissue to provide for accurate placement of a suture to attachthe graft to the mucoperiosteal flap.

FIG. 6 is a side view of the three-prong forceps 50 of the inventionshowing an orientation of the distal end of the forceps 50 wherein thepair of the grasping prongs 51, 61 feature forward directed teeth 54, 64for graft engagement and positioning. In use, the pair of teeth 54, 64engage the graft and hold the graft firmly in position relative to thelength of the forceps during graft introduction. Following suture of thegraft to the mucoperiosteal flap, the three-prong forceps 50 areatraumatically removed leaving the graft securely in place.

While the present invention has been particularly shown and describedwith respect to certain preferred and illustrative embodiments, it willbe understood by those skilled in the art that variations andmodifications may be made therein without departing from the spirit andscope of the present invention.

What is claimed is:
 1. A suite of surgical instruments for subperiostealtunneling comprising: a first elevator having a base portion comprisedof a handle having an ergonomic grip, a first elongated shaft region, asecond elongated shaft region and terminating in a distal curved andrectangular atraumatic tip; a second elevator having an ergonomic grip,a first elongated shaft region, a second shaft region having a curvedtransitional portion and terminating in a distal curved atraumatic tip,wherein a combination of an angled portion of the first elongated shaftregion and a second curved transitional portion and the second shaftregion have positive values for at least two angles along the length ofthe second elevator such that the distal curved atraumatic tip iscomprised of an arc region that disposes a most distal portion of thedistal tip outside an axis of the first elongated shaft region; and athird elevator having an ergonomic grip, and first, second, and thirdshaft regions having an angled portion therebetween such that the thirdshaft region has an angled portion relative to the first shaft regiongreater than 90° and less than 180°.
 2. The suite of surgicalinstruments of claim 1 wherein the first, second, or third elevators isfurther comprised of a mating fixture.
 3. The suite of surgicalinstruments of claim 1 wherein the first and second elongated shaftregions of the first elevator are oriented by angle having a rangebetween 0° and 45°.
 4. The suite of surgical instruments of claim 1wherein at least a portion of any shaft region of the first, second, orthird elevator is comprised of an anodized dark color for visualizationthrough tissue.
 5. The suite of surgical instruments claim 1 wherein thedistal curved atraumatic tip of the first elevator is comprised of anarc region.
 6. The suite of surgical instruments of claim 5, wherein thearc region of either the first or the second elevator is contiguous withthe second shaft region.
 7. The suite of surgical instruments of claim5, wherein the arc region of the first or second elevator is betweenapproximately one-eighth circle and approximately one-half circle. 8.The suite of surgical instruments of claim 1 wherein the third elevatoris comprised of a distal atraumatic tip proximate to the third shaftregion.
 9. The suite of surgical instruments of claim 1 wherein thefirst and second shaft regions of the third elevator are disposed in afirst plane and the third shaft region is disposed in a second plane.10. The suite of surgical instruments of claim 1, wherein the firstshaft region of the third elevator is disposed in a first plane and thesecond and third shaft regions of the third elevator are disposed in asecond plane.